Manufacture of artificial silk and other silk goods.



, rying out my invention sulfurous acid to pre- 3515 and supple or flexible The sulfurous acid.

To (LZZ whom it may concern:

\ Art of Manufacturing Artificial Silk, of which for its object to produce a brilliant and supple which will accomplish the object sought. For example, a suitable quantity of sulfurous acid may be dissolved in the acetone prior to, 'its'ultimate employment as the solvent, and when the filaments are formed from the -thewiscous compound in some convenient manner with sulfurous acid to produce the- UNITED STATES PATENT OFFICE.

HENRI ETIENNE ALFRED VITTLENETI, OF VILLEFRANCE-SUR-SAGNE,

FRANCE. r

MANUFACTURE OF ARTIFICIAL SILK AND OTHER S ILK GOODS.

Be it known that I, HENRI ETIENNE AL- FRED VITTENET, chemist, a citizen of the F; en'ch Republic, residing in Villefrancemr-Sane, Rhone, France, have invented certain new and useful Improvements in the the following is a specification. a,

This invention relates to the production of fibers or filaments of artificial silk; and it has or flexible filament from a viscous solution of nitrocellulose in acetone.

i A solution of pyroxylin or nitrocellulose in .acetone yields a viscous collodion which resembles in "appearance alcohol-ether collodion and which can be equally well formed in a known way into filaments or threads. The filaments, however, from the sol tion of pyroxylin in acetone'do not possess t e bril-' ancy and "s'uppleness of those from the alcohol-ether col odion, but, on the contrary, are rather opa ue, milky, or clouded and are far more britt e than the filaments of the latter. These defects appear to be due to a hydrate of a mixture of the acetone andnitrocellulose.

The purpose of the present invention is to remedy this defect of opacity and brittleness and to provide also for the easy recovery of the acetone. To thisjend I utilize in carvent hydration,and thus permit of the production of filaments or threads from the viscous compound which will,be brilliant may be employed in several ways, either of viscous compound they-'may be produced in the..;ai r, -in air mixed with sulfurous-acid gas, omen atmosphere formed of sulfurous acid al I, e,- or a solution of pyro'xylin in substantially-pure acetone in a viscous state may be formed into filaments in an atmosphere of sulfurous acid -gas. The object is to treat desired effect thereon.

Specification of Letters Patent.

Application filed July 19, 1905. Serial Ito-2203426.

A suitable and convenient mode of carry- Patented J an. 22, 1907.

ing out the invention in practice is to cause a current of sulfurous acid'to flow into the acetone until an increasein the weight of the mixture is attained which shall be e ual to the amount of the acid which it is desired to add to the acetone. The solution of sulfurou's acid in acetone thus obtained is then added to the pyroxylin in proportions which will vary with the degree of viscosity de-' sired, and this mixture is formed into 'filaments, as 'hereinbefore explained.

sulfurous acid gas ih employed because it gives to the filaments the required brilliancy,

translucency, and suppleness and because it permits of or facilitates the recovery of the acetone. To this end I may produce the filaments of the acetonic. collodion ina cur rent of sulfurous acid gas. It will suflice in order to recover the acetone to heat the combination of gases drawn 0E in an excess of;

rectlfy the aqueous -v soda and to roperly acetone thus 0 tained.

The acetone employed for dissolving the making thesolution, for the purpose specified. .3. The improvement in the art of producing filaments from a viscous solution of pyroxylin 1n acet0ne',iwh1ch cons sts 1naddlngsulfu'rous acid to the acetone, then dissolving the pyroxylin therein, and. then producing filaments from the solution in an atmosphere containing sulfurous acid. V f. v a

In witnessf f -I have hereiirito signed my name, th s -Stldd 7 presence of two subscribing witnessessy HENRI ETIENNE ALFRED virir'imnrf Witnesses MARWYAQH ayof June, 1905, in the ioc 

